Methods: Data was collected on the antimicrobial susceptibility of gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, and Pseudomonas aeruginosa) isolated from patients at the National Center for Child Health and Development from January 2010 to December 2014. Data on the first available isolate per person was analyzed by year. We also calculated DOT (Days of Therapy) per 1000 patient days, of antibiotics frequently used in our hospital (ampicillin/sulbactam, piperacillin/tazobactam, cefazolin, cefmetazole, cefotaxime, ceftazidime, cefepime, meropenem, gentamicin, and amikacin) by year, as a parameter of the amount of antimicrobial consumption. Then we analyzed the correlation between the DOT and the rate of resistance for the corresponding antibiotic using Spearman’s correlation.
Results: There were statistically significant correlations between the resistance rate of E. coli and the DOT of cefotaxime (r=0.900, p=0.037) and cefepime (r=0.900, p=0.037), but not meropenem, gentamicin or amikacin, and between the resistance rate of E. cloacae and the DOT of piperacillin/tazobactam (r=0.900, p=0.037), but not cefepime, meropenem, gentamicin or amikacin. In a subset of patient data, we confirmed that the resistance mechanism was primarily ESBLs production for E. coli, and AmpC beta-lactamases production for E. cloacae. However, we were unable to document such correlations for K. pneumoniae or P. aeruginosa.
Conclusion: The consumption of broad spectrum penicillins and cephalosporins appeared to select for ESBLs producing strains of E. coli and AmpC beta-lactamases producing strains of E. cloacae in the pediatric hospital setting.
S. Wakai, None
M. Komura, None
I. Miyairi, Dainippon sumitomo: speaker at a sponsored program , Speaker honorarium
Kyorin pharmaceuticals: speaker at sponsored lecture , Speaker honorarium
Astellas: speaker at sponsored lecture , Speaker honorarium
Teijin pharm: speaker at sponsored lecture , Speaker honorarium
Daiichi sankyo: speaker at sponsored lecture , Speaker honorarium
Takeda pharm: speaker at sponsored lecture , Speaker honorarium
Tanabe mitsubishi: speaker at sponsored lecture , Speaker honorarium
Janssen: Grant Investigator , Research grant